Right now, I'm in a small café near the Universität der Künste Berlin. It's obvious that great symphonies and the occasional revolution have been plotted here in caffeinated oblivion. The place has yellowing musical manuscripts on the walls and lit candles to go with my hot chocolate. Since I last wrote from Berlin, I've wandered around the city and seen many of the sights: two stand out.

The first is the East Side Gallery, a painted remnant of the wall that's about ten minutes walk from where I'm staying. The gallery extends at least a kilometre and is filled with colour, freedom, love and hope. I wish I could write down all that it made me feel, but I can't reach quite that far yet.

The second is a war memorial to all those who've died in any war, on the way to Brandenburg Tor from Alexanderplatz. From the outside, it's a simple brown stone building. What's impressive is the inside.

As you walk through the door, you see a dark room with high ceilings. The floor and walls are the kind of black-grey that reminds you of smoke, ash and death. The room itself is bare except for a statue in the middle, that looks like a person sitting. You can't make out the face or sex of the figuce, but you know she must be weeping for her dead child. When I first stepped in, the only thing I could think was, "Oh God, what have we done?".

I've been in buildings that were supposed to elevate the mind toward heaven, in houses that we designed to make me feel at home, cafes that make me feel more creative than I am and even haunted houses designed to make me feel scared. Until this week, I've never been in a building that conjures up the mix of grief and horror that comes from knowing that something is deeply, deeply wrong the human race and that I am a part of it.